Racial Disparities in Immunization Coverage Levels Among Children Aged 24 Months — Tennessee

Learning Objectives for this Presentation:
By the end of the presentation participants will be able to understand immunization disparities in Tennessee

Background:
Since 1980, the Tennessee Immunization Program has conducted annual surveys to estimate immunization status of Tennessee residents aged 24 months; no rigorous statistical analysis of racial differences was performed.

Objectives:
To analyze immunization coverage of black and white 24-month-olds born January–March 2005.

Methods:
A survey sample (n = 1,585), drawn from birth certificates of residents born January–March 2005 was oversampled for blacks. Exclusion criteria included state relocation, refusal to participate, or death (n = 102). Non-white or non-black races (n = 32) were excluded from this analysis. Children not located were included (n = 29) as incompletely immunized. Immunization history was gathered from the Tennessee Immunization Registry. For children with incomplete immunization histories, parents/guardians and immunization providers were contacted for immunization dates.
The 4:3:1:3:3:1 immunization series is defined by the following immunization doses: 4 diphtheria and tetanus toxoids and acellular pertussis (DTaP) or tetanus and diphtheria (DT); 3 polio; 1 measles, mumps, rubella; 3 Haemophilus influenzae type B; 3 hepatitis B; and 1 varicella.

Results:
White children were more likely to complete the 4:3:1:3:3:1 series than black children by age 24 months (84.2% [1,005/1,194] versus 77.0% [198/257]; relative difference {RD}: 8.6; odds ratio {OR}: 1.6 [confidence interval {CI}, 1.1–2.2]; P = 0.006). DTaP has the widest disparity in immunization of all six vaccines. White children were more likely to have completed 4 doses of DTaP (87.9% [1,050/1,194] versus 80.9% [208/257]; RD: 8.0; OR: 1.7 [CI, 1.2–2.5]; P = 0.003). Seventeen of 1,194 (1.4%) white children and 12 of 257 (4.7%) black children were not located (categorized as incompletely immunized).

Conclusions:
Differences in immunization rates between black and white children aged 24 months were detected in the 2007 survey. Tennessee will raise awareness of this disparity among immunization providers.